Field of the Invention
The present disclosure relates to a device for manufacturing an interior material having a hollow therein. More particularly, it relates to a device for manufacturing an interior material having a hollow, which is used for preventing a cloth from being creased at the time of manufacturing the interior material manufactured to have the cloth on the surface thereof.
Description of Related Art
In general, an interior material serving as both finishing and an ornament for an internal surface is attached to fronts of a driverime oat and a passenger's seat and the inside of a door in an interior of a vehicle and the interior material is manufactured by considering various requirement performance including durability, texture, the sense of touch, a sense of beauty, stability, and the like.
FIG. 1 is an exemplary diagram illustrating a method for manufacturing an interior material for a vehicle in the related art.
Referring to FIG. 1, in the related art, a cloth 3 is inserted between an upper mold 1 and a lower mold 2 of a mold for injection body forming of the interior material and the mold is closed and thereafter, a plastic resin is injected between the cloth 2 and the lower mold 3 in the closed mold to injection-form an injection body, thereby manufacturing an interior material constituted by the injection body having the cloth on the surface thereof.
However, when the interior material is manufactured by the method in the related art, since a mold having a resin injection hole (alternatively, gate) is used only at a location, injection pressure of the plastic resin needs to increase as the shape of the injection body is larger, and the cloth cannot be resistant to the injection pressure with the increase of the injection pressure, and as a result, problems such as surface damage and resin leakage (the resin leaks out of the cloth) occur.
When the interior material is manufactured by the method in the related art, since it is impossible to control a filling direction of the resin injected into the mold, the cloth is creased or the resin cannot be generally filled between the lower mold and the cloth at the time of manufacturing the injection body having a complicated shape, and a distance which the resin that is filled through the resin injection hole reaches in order to complete forming of the injection body is too far and as a result, a problem such as hardening of the resin before forming the injection body is completed occurs, thereby making the forming of the injection body be difficult.
In order to solve the problem, the interior material constituted by the injection body having the large size or the injection body having the complicated shape is manufactured while being divided into two or more and in this case, as the number of parts increases, the number of processes increases and a problem is caused, in which exterior marketability deteriorates due to a connection portion between the separately manufactured parts.
Meanwhile, FIG. 2 is a diagram for describing a problem which occurs at the time of manufacturing an interior material having a hollow therein by the method for manufacturing the interior material in the related art and FIG. 3 is a diagram for describing a problem which occurs at the time of manufacturing the interior material by using a mold having two or more resin injection holes in the related art.
As illustrated in FIG. 2, in order to form the injection body of the interior material having the hollow therein, when the injection body of the interior material is intended to be formed by injecting the plastic resin between the cloth input into the mold and the lower mold as described above, since the plastic resin filled between the cloth and the lower mold needs to be injected while continuously maintaining high pressure and temperature, the high pressure and temperature are continuously applied to the edge of the resin injection hole until the resin reaches a final point (a point in which the plastic resin injected from the resin injection hole needs to finally reach in order to complete forming the injection body, and as a result, the cloth is damaged due to the high pressure and high heat.
Since it is impossible to predict a flowing direction of the resin filled between the cloth and the lower mold, when the resin permeates the cloth, pulling, slack, crease, and the like of the cloth occur in the flowing direction of the resin.
Since the cloth is exposed on the surface of the interior material to form an exterior when the interior material is applied to a vehicle body, marketability deteriorates when the cloth is creased and damaged.
In order to solve the problem, when the interior material is manufactured by using the mold having two or more resin injection holes, as the plastic resin is injected simultaneously through the plurality of resin injection holes as illustrated in FIG. 3, the resins injected through the respective resin injection holes collide with each other, and the cloth is creased and depressed at collision points and further, since it is still impossible to control the flowing direction of the resin even though two or more resin injection holes are used, there is a possibility that the pulling, the slack, the crease, and the like of the cloth will occur at a predetermined point.
For reference, in FIGS. 2 and 3, reference numeral 4 represents an area where the resin is filled between the cloth (alternatively, upper mold) and the lower mold at the time of forming the injection body of the interior material having the hollow therein and reference numeral 5 represents a area where the resin is not filled between the cloth (alternatively, upper mold) and the lower mold at the time of forming the injection body of the interior material having the hollow therein.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.